Brothers Trucks Chevy C10 Shortbed - Short For Sport

Shortening the frame of a longbed truck down to the specs of a shortbed isn't exactly a new idea, in fact, we've even done just that in years' past. But with the availability of shortbed trucks drying up or going for big dollars while longbed trucks can be had for pennies on the dollar, it's a good thing to revisit from time to time to remind people that there are other options than spending $12k on a starter truck.

When I originally set out to look for a project truck, I purposely looked for a longbed, not only because I'm cheap, but because I wanted to show you great readers just what could be done to one. I made the promise not to immediately cut it up as I wanted to get it to a somewhat finished level before doing so. Well, the time has come and I've put about 5,000 miles on the old Laggard Longbed, so suffice to say, it's time to get a cuttin'.

Cutting down a longbed frame to shortbed specs isn't rocket science per se, for all that's required is to take a 12-inch section out of the middle and an 8-inch section of the back, pretty straight forward come to think of it. There are, however, a couple different locations on the framerails where it's possible to remove the 12-inch section required to trim the wheelbase down from 127 inches to the shortbed's specs of 115 inches.

One is to remove the section from in between the cab mounts, directly under the cab. This makes the job nice and easy as the frame is perfectly straight here, giving you plenty of area in which to work. It also retains the stock crossmember in the back portion of the frame, alleviating the job of removing all those rivets and moving the crossmember itself. Simply hack out the 12-inch section, along with the cab mount and slide everything forward. The front bed mount needs to be removed and the cab mount reattached once the frame is moved forward, but all in all it's a pretty simple task. That is, however, unless the cab and front sheetmetal need to stay in place. Then it becomes awfully difficult.

Originally, that was our plan when we teamed up with Brothers Trucks to do this story. They hooked us up with everything we needed for the chassis, including a cab mount kit, new rear cab mounts, and boxing plates for the frame, as well as a new bed assembly. Upon further inspection, however, it became painfully obvious that it was going to be too much work to try to remove everything that stood in our way in order to make the cuts under the cab. It simply turned a two-day job into a week-plus affair by the time you factored in gapping and bolting back up all the sheetmetal.

Shifting gears, we decided to take the section out from between the cab mount and what will become the front bed mount, right in front of the rear kick. As it turns out, the existing front bed mount gets cast aside and the second bed mount scoots forward exactly 12 inches to take its place. The rear cab mount needs to be removed as the front cut line is right through its location, but it's easily reattached in the same spot once the front and rear frame halves are reattached.

The only drawback for stock applications is that the trailing arm crossmember will need to be relocated. In our case, this was a simple task as we had previously installed a CPP bolt-in crossmember. If you've got a stock crossmember, this would be a good time to swap it out with a new CPP unit. This also yielded a little bonus once I started mapping out where the crossmember would be relocated. Given the proximity to the seam and using the boxing plates provided by Brothers, I'd be able to mate the boxing plates to the crossmember while completely traversing the cutline, making a super strong structure over the entire area. I love it when a plan works out!

This month, I'm going to cover the ins and outs of how I shortened the frame, illustrating a couple of tips and tricks I found out along the way, and we'll come back and assemble all the sheetmetal and get the truck back on the ground. From there it'll be time to coat the inner bed panels before installing a new wood kit from Bed Wood & Parts in a couple months. And I can't be seen driving around some kind of cheesy circus wagon, so then it'll be off to get a coupla' coats of fresh paint.

Of course all this cuttin' and grindin' isn't just done for fun; there are a few arguments to be made in favor of both. For starters, I really enjoyed the 8-foot longbed when it came to hauling stuff and it rode really nice given the long wheelbase and extra weight. But when it came to being a sporty hot rod of any kind, that just wasn't happening. Not being in the junk hauling business, I figured that aesthetics, handling, and drivability should win out on this project as I can still haul stuff with the shorter bed, it'll just look better and be much more fun doing so!

1. Here's the tailgate view of the old 8-foot bed. She's well worn, but still in great shape. Unfortunately, she's gotta go.

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2. Removing eight bolts is all it takes before the bed can be lifted off the frame. A tie strap, a couple of wires and a forklift make quick work of the job, but a couple buddies could do it just the same.

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3-4. Regardless of where you decide to cut the chassis, you're going to need to take 12 inches out of somewhere between the front cab mount and the start of the rear kickup. You can see why it can be simpler to take it out of the section between the cab mounts, as it's nice and straight with nothing in the way. Working in this area, however, requires lifting the cab a substantial amount, which can open up a can of worms.

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5. Alternatively, if the cab needs to stay in place, the section can be removed from behind the cab as well. This method allows easy access to the work area. A carpenter's square yields perfect, parallel 45-degree cut lines. This is the section we'll be removing.

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6-7. Regardless of where you decide to take the section out, it will be necessary to remove both the rear cab mounts as well as the front bed mount.

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8. This photo illustrates how the second bed mount becomes the front bed mount once the 12-inch section is removed from the frame.

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9. If the cut is made behind the cab, it will be necessary to remove the crossmember and relocate it forward of the cut line. If the cut is made under the cab, this is not necessary as the crossmember slides forward with the rear section of the chassis. This is one of those "six of one, half dozen the other" kinds of situations as it really comes down to whether one wants to remove the cab or move the crossmember.

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10. With our cut lines marked, it's time to set the chassis up nice and level. This is markedly more difficult as eight jack stands are used to support both ends of the truck once the cut is made. The jackstands in the middle need to be nice and snug against the bottom of the frame so that nothing moves once the frame is separated.

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11. Anytime I do any chassis work, I like to keep things level, both side to side and front to back, that way your eyes don't play tricks on you and you always have a baseline to work off of. If things look like they're moving once the welding begins, all it takes is a level to double check it as opposed to trying to remember what degree rake it was set at.

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12. Once everything is level and square, the hacking can commence. I used a bi-metal blade in a reciprocating saw to make the straight cuts on the top and bottom of the framerail.

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13. Then, I used a Lincoln Tomahawk plasma cutter, drug along a spare piece of 116-inch steel as a guide, to make the vertical 45-degree cut. You can just make out the 18-inch hole I made where the top and side cuts will meet. This prevents any overcutting and gives the blade and the plasma cutter room to stop without cutting needlessly into the surrounding material.

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14-15. And there you have it, the point of no return! That's a full 12 inches taken out of the framerail.

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16. One of the drawbacks of doing suspension/chassis mods with the bodywork still on the truck is the fact that it can be difficult to take long or triangulated measurements from one end to the other. To solve this, a plumb bob can be used to mark the floor of the shop, where the measurements can be taken instead. Here, I'm marking the centerline of the front spindles so that I can double check the wheelbase reading once the rear portion of the frame is moved forward.

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17. I also used the plumb bob to locate the front cab mounts as well as the front core support mounts to take further measurements once the frame is aligned. A pair of straight edges (bed cross sills work great) spanning the marks on either side of the truck can then be measured to give us different parameters. Here, the distance between the front cab mounts and the front bed mounts are compared for parallel.

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18. With the back half of the frame level and parallel to the rest of the chassis, the two sections can be tacked together before making a final pass with the tape measure. What did my old shop teacher say? "Measure twice, cut once." I prefer "measure 10 times, cut once, then measure a couple more times just to be sure."

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19. Before I tacked the front and rear portion of the chassis together, I installed a fish plate to the front portion, that way I had something to clamp the rear half to while I made my finite adjustments. Here, the final welding of the two sections has begun. Moving your weld around prevents overheating the area, decreasing the likelihood of any warping taking place.

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20. The opposite side framerail shows the finished fish plate.

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21. With the fish plates welded up and the outside of the seam tack welded, our attention is turned to the boxing plates from Brothers Trucks. Note that the crossmember has been welded into place and that the boxing plates will mate to it as well as spanning the entire length of the seam, providing a super strong structure.

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22. Once the boxing plates are welded up, I fired up the TIG welder to hit the outside seams. I opted for the TIG for this step because it's easier to grind down flush and I wanted a clean edge to my framerail. At this point, the joining of the two sections is complete and if you've measured correctly, you should have a 115-inch wheelbase frame.

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23. The job's not quite done, however, as we still need to remove an additional 8 inches from the back of the framehorns.

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24. I cut the entire length using a Sawzall as it yields a nice, straight cut.

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25. Next, the rear bed sill plate attachment hole needs to be drilled. The cutoff section of the framehorn can be used as a template.

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26. Two holes drilled the corresponding diameter coupled with a few minutes' worth of filing results in an elongated hole just like the factory's.

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27. The last step before we wrap up the fabrication portion of the shortbed conversion is to attach the new Brothers Trucks cab mounts. This is how the cab mounts should be assembled.

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28. Using the front two cab mount holes that remained untouched on the front half of the chassis to locate the rear cab mount, it was a simple matter of welding them in place before installing the bushings and lowering the cab back in place.

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29. With the new bed from Brothers Trucks loosely assembled, the result is pretty impressive. A full 20 inches shorter with a foot taken out of the wheelbase should result in a totally different driving experience, not to mention a more sporty aesthetic.